Matthew recalled his visits to lower Manhattan as a kid, long before 9/11.

“I thought it was kind of cool. I remember as a kid growing up in New York City and visiting the World Trade Center, as it was before,” he said. “And now I get a chance to work in the building.”

Work crews are still putting finishing touches on the 1,776-foot skyscraper, with the 102nd-floor observation deck due to open this spring.

John Duffy, director of policy and control at Conde Nast, admitted some of his colleagues were nervous about setting foot in the new WTC — but most were overjoyed to be part of this downtown revival.

“It’s just a great start. I think some people are nervous, but most people are just excited to start downtown. I used to work here in the ’80s in the original Trade Center, so it’s sort of like coming home for me,” he said.

The north facade of One World Trade CenterAFP/Getty Images

“I’m not really concerned about it (security). The Port Authority has this place buttoned up. (I’m) just excited. Just excited to get started. We’re helping to revitalize downtown.”

Vijay Ramcharitar, a 25-year-old finance analyst on the 21st floor, said he loves his office view — even if he’s staring down any lingering security fears.

“The view from over there is great. I could understand the fear behind it, but fear is something they (terrorists) want you to live with,” Ramcharitar said.

“If you live with fear, you can’t get anything done. I don’t think you look at this building with fear, you look at it with inspiration.”

Maryanne Casey, a corporate paralegal at Conde Nast, said she couldn’t help thinking of her family on the way into work on Monday.

Her sister worked at 7 World Trade Center and her FDNY brother spent days working “on the pile” in the aftermath of 9/11.

“I think it’s spectacular,” Casey said of her new work digs. “And I think it’s a great tribute to America to see this. I’m proud to be able to work here.”

A woman uses her ID card to enter One World Trade Center on Nov. 3.AFP/Getty Images

The sparkling new building is the tallest in the Western Hemisphere and cost $3.9 billion to build. It had originally been slated to open in 2006, but cost overruns and political infighting led to delays.

Other new tenants include the General Services Administration and the ad firm Kids Creative.